The invention relates to the combination of an overrunning clutch of the sprag type with a deep-groove ball bearing.
German Pat. No. 1,264,886 discloses an overrunning clutch in which the balls and sprags are arranged alternately between a common inner race and an outer race. The balls may run in a raceway in alignment with the common central radial plane of the races and the individual sprags which are spring-biased in the direction of engagement and are pivotable about axes extending parallel to the bearing axis, are disposed between the balls in pairs to cooperate with the remaining race shoulders on both sides of the ball raceway. The sprags and balls have a common cage ring comprising two radial halves which adjoin each other in the region of the radial running plane of the balls. The two inward-facing axial faces of the cage ring halves are provided with pockets for the balls and the two outward-facing axial faces are provided with pockets for the sprags. The last-mentioned pockets are closed at the end of the assembling operation by the fitting of circular cover discs.
The above-outlined construction therefore calls for the manufacture and storage of three different components for making the cage ring, because, although the cover discs are identical, the two above-mentioned cage ring halves cannot be identical, since the spring biasing of the sprags calls for compression springs which must be differently arranged in the two cage ring halves. Furthermore, the use of compression springs for the sprags has the disadvantage that due to manufacturing tolerances, the springs may apply widely differing biasing forces to the sprags. This, in turn, may lead to a non-uniform operation of the sprags and thus, to an irregular loading of the overrunning clutch along its circumference.
Although the two cage ring halves and their cover discs are centered with respect to each other by recesses and studs on their boundary surfaces, the retention of the parts, however, can be ensured only by welding or adhesively bonding them together. This calls for exceptional skill in the assembly and therefore, this is an operation which can be performed only by reliable skilled personnel; a fact which has a noticeable effect on the prime costs. Furthermore, it is not possible to dismantle the known cage ring without destruction, for example, for the purpose of testing the operability of the overrunning clutch or the ball bearing.